Something big is happening on the sun. The sun's global magnetic field is about to flip, a sign that Solar Max has arrived. Courtesy: NASA sciencecast

This image provided by NASA, captured by the Solar Dynamics Observatory, shows an M9-class solar flare erupting on the Sun's north-eastern hemisphere at 03:49 UT, just four days after a previous strong CME that sparked aurora around the world on 22/01/2012. Picture: AFP Source: News Limited

THE sun's huge magnetic field is about to flip, according to NASA.

The magnetic field is so big it extends billions of kilometres past Pluto, and NASA says its change will have ripple effects across the entire solar system as it changes between the sun's north and south poles.

Stanford University solar physicist Phil Scherrer said that while earth orbited the sun, it dips in and out of what solar physicists call the "current sheet" - an electrical current jutting out from the sun's equator.

While the magnetic field is changing polarity, the current sheet becomes wavy, which stirs up stormy space weather.

"The sun's polar magnetic fields weaken, go to zero, and then emerge again with the opposite polarity," Professor Scherrer said.

"The sun's north pole has already changed sign, while the south pole is racing to catch up."

The phenomenon will mark the middle of Solar Cycle 24.

But don't worry, it happens about every 11 years, so it's not going to be the end of the earth.

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